Variable pitch and width jaw for track presses

ABSTRACT

A variable pitch and width jaw for use in a track press employed in the assembly and disassembly of drive chains for the ground engaging shoes in track laying tractors.

United States Patent Robinson Sept. 9, 197 S [54] VARIABLE PITCH AND WIDTH JAW FOR 3,075,346 1/1963 Quarve 59/7 TRACK PRESSES 3,075,347 1/1963 Bonifas 59/7 3,099,130 7/1963 Pahl 59/1 I [75] inventor: George L. Robinson, San Mateo. 3 553,9 0 1/1971 Ellefson (3311f. 3,820,224 6/1974 OCallaghan 59/1 1 [73] Assignee: Wolff Manufacturing Company,

Burlingame. Calif. Primary ExaminerLowell A. Larson [22] Filed, June 28 1974 Assistant Examiner-Gene P. Crosby Appl. No.: 483,980

US. Cl 59/7; 59/11 Int. Cl. B21L 9/06 Field of Search 59/7, 11, 5, 8, 34

References Cited UNITED STATES PATENTS Childs 59/7 [57] ABSTRACT A variable pitch and width jaw for use in a track press employed in the assembly and disassembly of drive chains for the ground engaging shoes in track laying tractors.

5 Claims, 7 Drawing Figures PATENTEDSEP 9m: 3.903588 SHEET 2 UF 4 VARIABLE PITCH AND WIDTH .lAW FOR TRACK PRESSES BACKGROUND OF THE INVENTION This invention relates generally to jaws for use in track presses and more particularly to variable pitch and variable width jaws for use in track presses to accommodate drive chains having various pitch and width.

Crawler or track laying tractors are widely used particularly for heavy duty work. The tracks employed in such tractors include ground engaging shoes or grousers removably secured to a drive chain driven over an idler sprocket by means of a driven sprocket. The drive chain includes a plurality of sections each adapted to receive a shoe. Each section includes a pair of side links spaced apart to receive the sprocket wheel teethv Each section is pivotally joined to the next adjacent section by means ofa cross pin and bushings. The side links of each section are relatively widely spaced at one end to receive the relatively closely spaced ends of the next side link. Bushings are press fit into the closely spaced ends while pins are press fit into the widely spaced ends of each pair to form the joint between sections.

Because of the nature and operation of tractors, the tracks are subjected to rapid wear and require frequent repair. Generally, for repair, the complete track is removed from the tractor by removal of a master pin and the track is laid out. In larger tracks the shoes or grousers are removed to expose the drive chain. In smaller tracks they are not removed. In either case, the chain is then fed to a track press to present the links in succession to a work station which includes a saddle, anvil or jaw (hereinafter jaw) for receiving spaced adjacent bushings of the chain in position as hydraulic rams move tools into cooperative relationship with the pins and bushings to remove the pins and bushings from the links to release the side links. The track press generally includes hydraulic driven tools on each side of the chain whereby to remove the pins and bushings from each side of the links in succession. The links are prevented from moving from side to side by the jaw which includes spaced U-shaped grooves for receiving the bushings and orienting each section in a position whereby the advancing tools register with the pins and bushings during the pressing operation. The jaw also prevents lateral movement of the links whereby the track press can operate efficiently upon the bushings and pins. The jaw may be a retractable jaw which is retracted to advance the chain one section at a time to present the next section to the station or may be a fixed jaw where the chain is moved upwardly, advanced and then lowered to place the bushings in engagement with the jaw grooves. In either instance, the size of the U- shaped groove must conform to that of the bushing and the spacing of the groove must conform to the pitch, distance between bushings, of the chain and the lateral Spacing of the links. A typical track press with retractable jaws is described in US. Pat. No. 3.075,346.

There are many models of track laying tractors manufactured by each of a number of manufacturers. The track size of the various size tractors, of course, varies both as to the pitch and width of the drive chain and size of the bushings. As a result, a separate jaw must be available for each size track and bushing to provide the proper distance between the saddles (grooves) to ac commodate the bushings and position the chain and proper width to minimize lateral movement during a pressing operation. The jaws are relatively large, heavy and cumbersome and it is desirable to limit the number which must be stored to reduce the investment in jaws and storage space. It is, of course, also time consuming to change the jaws for each different drive chain. It is, therefore, important that the number of jaws required in connection with any track press be minimized.

OBJECTS AND SUMMARY OF THE INVENTION It is a general object of the present invention to provide ajaw assembly which can be used for a large number of different chain sizes and types.

It is another object of the present invention to provide a jaw which comprises two sections which may be spaced from one another to accommodate drive chains having widely different pitch.

It is a further object of the present invention to provide a jaw having removable side plates to accommo date drive chains having different widths.

It is a further object of the present invention to provide a track jaw which includes V-shapcd grooves or saddles whereby to accommodate and accurately position bushings of various diameters.

The foregoing and other objects of the invention are achieved by a jaw which includes first and second portions each including a groove and adapted to be spaced from one another to vary the distance between the grooves and which include means for receiving and holding side plates whereby to vary the width of the BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a perspective view showing a track press incorporating ajaw in accordance with the present invention.

FIG. 2 is a plan view showing a track press and a jaw in accordance with the present invention.

FIG. 3 is a perspective view of a jaw having fixed width and constructed in accordance with the invention.

FIG. 4 shows ajaw similar to that shown in FIG. 3 but including different mounting means.

FIG. 5 is a perspective view of an adjustable pitch jaw including side plates for varying the width of the jaw as well as the pitch.

FIG. 6 is an enlarged side elevational view of a side plate.

FIG. 7 is an end view of the side plate shown in FIG. 6.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, there is shown a track press including hydraulically driven tool heads 12 and 13 adapted to accommodate tools 16 and 17 respectively. The tool I3 is shown in the advanced position in engagement with the bushing and the pin of the link 18 to thereby remove the bushing and pin and release the link 18. Thereafter, the tool 13 is retracted and the tool 16 advanced to engage and remove the bushing and pin of the associated link. The jaw 21 is then retracted, the drive chain advanced by one pitch length, the jaw raised to engage the bushings and the process repeated to release the links for the next section of track.

Suitable control 22 is provided for retracting the jaw. Control 23 is provided for hydraulically advancing the drive chain. Controls 24 and 26 control the left and right-hand rams for advancing the tools to remove the bushings and pins. Work tables 27 and 28 accommodate the release links and are adjustable by means of adjusting screws 29 and 31 respectively.

Referring more particularly to FIG. 2, two sections of chain are shown each including spaced links l and 16 with the narrow ends of the links joined by the bushing 32 and the wide ends of the links by pin 33. As previously described, each link is individually released by pressing out the bushing on the narrow end simultaneously with the pin on the wide end whereby to release the link.

In accordance with the present invention, the jaw 21 is formed with first and second sections 36 and 37, FIGS. 1 and 2, mounted on jaw support 38 by means of bolts 39. Each of the sections 36 and 37 includes elongated holes 41 whereby the spacing between the sections 36 and 37 may be adjusted to vary the distance between the V" grooves 42 and 43. The V grooves serve to receive bushings and because of the inclined surfaces also serve to center the bushings therein. The spacing of the sections 36 and 37 is adjustable to accommodate the different pitches encountered for different size chains whereby a large number of chains may be accommodated by simply adjusting the spacing. The V" groove not only centers but also serves to accommodate bushings having different amounts of wear whereby to provide an accurate spacing and alignment with the adjacent tools 16 and 17.

FIG. 4 shows another means for mounting the sections for movement towards and away from one another. ln the embodiment of FIG. 4, the lower edge of the jaw sections 36a and 370 are inclined outwardly and received by the dovetail members 46 and 47 which are secured by bolts 48 whereby to tighten the members 46 and 47 against the inclined surfaces and lock the jaw sections into position.

In certain instances it is preferable that the jaws not only accommodate track sections having different lengths but also accommodate track sections having links having different spacing. For this purpose, the sections 36 and 37 are formed such as shown at 36b and 37b wherein each of the sections is provided with a lateral large hole 61 and a smaller hole 62. Threaded holes 63 and 64 accommodate set screws. Side plates 66 and 67, FIGS. 6 and 7, include plate portions 71 and pins 72 and 73 which are accommodated in holes 61 and 62. The pins are suitably fastened to the plates as by welding. After the pins 72 and 73 are placed in the openings 61 and 62 in the threaded wells, set screws 63 and 64 are tightened to engage the pins and hold the plates. Thus, by having a plurality of plates of different thicknesses, it is possible to accommodate track sections having different widths. It is apparent that the holes 61 and 62 and pins 72 and 73 may be of the same size.

As a consequence, it-is seen that the jaw is not only adjustable as to pitch but as to width and serves to accommodate a large variety of chain sizes by merely adjusting the spacing between the sections and by inserting plates of suitable thickness. The V" groove can accommodate bushings of different sizes or wear and is useful in connection with conventional jaws. This, of course, lowers the required number of jaws which must be maintained in storage for accommodating different track sizes, reduces the investment in jaws and economizes in the amount of material which must be used for jaws.

I claim:

1. A variable pitch jaw for use in a track press for removing side links in drive chains of the type having a plurality of sections each including spaced side links joined to one another by pins and bushings in which the drive chain is longitudinally positioned and laterally restrained by a jaw which fits between links and accommodates adjacent bushings, the improvement comprising a jaw assembly including first and second jaw sections each including a transverse groove for accommodating the bushing of adjacent chain sections and means for adjustably mounting said jaw sections whereby said sections can be moved towards and away from one another to accommodate adjacent bushings having different spacing.

2. A jaw assembly as in claim 1 wherein said grooves are V shaped for accommodating bushings having different diameters and wear.

3. A jaw assembly as in claim 1 in which each section includes means for accommodating and holding plates adapted to be disposed on each side of said jaw to adjust the width of said jaw.

4. A jaw as in claim 1 wherein said means for adjusting the spacing between jaws includes elongate holes.

5. A jaw assembly for use in a track press for removing side links in drive chains of the type having a plurality of sections each including spaced side links joined to one another by pins and bushings in which the drive chain is longitudinally positioned and laterally restrained by a jaw which fits between links and accommodates adjacent bushings, the improvement comprising a two-piece jaw, each piece including spaced transverse V" shaped grooves for accommodating the bushing of adjacent chain sections, said "V shaped grooves permitting the jaw to accommodate bushings having different diameters and wear.

* I. k IR 

1. A variable pitch jaw for use in a track press for removing side links in drive chains of the type having a plurality of sections each including spaced side links joined to one another by pins and bushings in which the drive chain is longitudinally positioned and laterally restrained by a jaw which fits between links and accommodates adjacent bushings, the improvement comprising a jaw assembly including first and second jaw sections each including a transverse groove for accommodating the bushing of adjacent chain sections and means for adjustably mounting said jaw sections whereby said sections can be moved towards and away from one another to accommodate adjacent bushings having different spacing.
 2. A jaw assembly as in claim 1 wherein said grooves are ''''V'''' shaped for accommodating bushings having different diameters and wear.
 3. A jaw assembly as in claim 1 in which each section includes means for accommodating and holding plates adapted to be disposed on each side of said jaw to adjust the width of said jaw.
 4. A jaw as in claim 1 wherein said means for adjusting the spacing between jaws includes elongate holes.
 5. A jaw assembly for use in a track press for removing side links in drivE chains of the type having a plurality of sections each including spaced side links joined to one another by pins and bushings in which the drive chain is longitudinally positioned and laterally restrained by a jaw which fits between links and accommodates adjacent bushings, the improvement comprising a two-piece jaw, each piece including spaced transverse ''''V'''' shaped grooves for accommodating the bushing of adjacent chain sections, said ''''V'''' shaped grooves permitting the jaw to accommodate bushings having different diameters and wear. 